Our long term aim is to elucidate the mechanisms whereby odors produce the sensation of smell. The present application is focused on one of the early steps in this process: the transduction of odors into an electrical response in olfactory receptor cells. Specifically, we propose to investigate the role of intracellular messengers in olfactory transduction. There is presently evidence that olfactory transduction is mediated by both intracellular messenger-dependent and -independent mechanisms. We propose a novel approach, that is, to use the patch clamp technique to study both the conductive properties of olfactory cilia as well as the electrical responses of intact receptor cells to odors. Our results will be novel and are likely to provide unequivocal evidence concerning the role of intracellular messengers in olfactory transduction. Such data may also be useful in understanding the mechanisms of toxicity of anosmia-producing agents in the environment, and therefore may lead to improvements in our understanding of the physiology and pathology of the olfactory epithelium.